Echinococcus granulosus glycoconjugates induce peritoneal B cell differentiation into antibody‐secreting cells and cytokine production

• Published in: Parasite immunology 2011-11, Vol.33 (11), p.621-631
• Main Authors: MOURGLIA‐ETTLIN, G., AMEZCUA‐VESELY, M. C., FRAGA, R., BAZ, A., MERINO, M. C., GRUPPI, A., DEMATTEIS, S.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Helminth - biosynthesis; Antibodies, Helminth - immunology; Antigens, Helminth - immunology; B-Lymphocytes - immunology; B-Lymphocytes - metabolism; Cell Differentiation; Cells, Cultured; cytokines; Echinococcosis - immunology; Echinococcosis - parasitology; Echinococcus granulosus; Echinococcus granulosus - immunology; Echinococcus granulosus - metabolism; Female; glycoconjugates; Glycoconjugates - immunology; Host-Parasite Interactions; Interleukin-10 - biosynthesis; Interleukin-10 - immunology; Interleukin-6 - biosynthesis; Interleukin-6 - immunology; Lymphocyte Activation; Mice; Mice, Inbred BALB C; peritoneal B cells; Peritoneum - immunology; Tumor Necrosis Factor-alpha - biosynthesis; Tumor Necrosis Factor-alpha - immunology
• ISSN: 0141-9838; 1365-3024
• DOI: 10.1111/j.1365-3024.2011.01326.x

Summary Helminth parasite infections are associated with predominant Th2‐type cytokine responses, and parasite glycoconjugates have been recognized as partially responsible for such immune bias. It has been proved that Echinococcus granulosus evokes a Th2‐type cytokine pattern characterized by a high production of IL‐4, IL‐5, IL‐6 and IL‐10, and no or mild IFN‐γ levels in animal models and in patients with cystic echinococcosis, respectively. Here, we show that E4+ (a glycoconjugate‐enriched fraction from E. granulosus protoscolex) stimulated the secretion of a high concentration of IL‐6, followed by IL‐10 and TNF‐α by normal peritoneal B cells. We determined that E4+ bound to the surface of peritoneal B cells and induced their activation and, also, triggered the differentiation of peritoneal B cells into IgM‐, IgG2b‐ and IgG3‐secreting cells in a T‐independent way. Interestingly, the IgM released by E4+‐stimulated peritoneal B cells from normal mice recognized protoscolex antigens. Results showed that, after the encounter with antigens from E. granulosus protoscolex, peritonealB cells are a source of Th2‐type cytokines and polyclonal antibodies, some of which recognize parasite antigens, suggesting that peritoneal B cells can condition the outcome of the infection.